Recovering Silver from Crushed Ore?

[Ferrell]

We had an assay done on some ore and discovered both gold and silver in microscopic amts, but enough to pay to use a chemical process to recover the gold. Should we try to recover the silver before we do the gold recovery? Can anyone point me to a thread or instructions on what process to use to recover silver from crushed ore? We have approx 4 ounces per ton of raw material and would be processing ourselves as we have time. The gold will be our first consideration, but if we decide to go after the silver as well, we've heard it needs to come out first. Right or wrong, or does it matter? And any help in HOW to recover it would be so appreciated. Thanks!

Allen and Miralee

 

[jimdoc]

Anything to do with ore you should post in the Prospecting, Mining, Ore Concentrates & Geochemical section to get the best answers.

A moderator can move this there for you when they get a chance.

Jim

 

[Ferrell]

Oh, sorry. I saw that the thread I posted this in was anything to do with silver, so I assumed my question would be appropriate. Thank you for offering to move it.

 

[jimdoc]

The people likely to be able to give you the best advice may only check this section. I think GSP moved it for you.

Jim

 

[Ferrell]

Thanks, Jim and moderator!

 

[Harold_V]

Without knowing a great deal about the ore in question, you're not likely to get much useful advice here. Extracting gold and silver from ores isn't a cut and dried process---there are many ways to achieve the end, each dependent on the type of ore.

Frankly, unless your ore (fire) assays at least a few ounces of gold per ton, you can spin your wheels endlessly and never make a dime. Large corporations process ore that is as low as .10 ounce/ton and make a profit, but they also handle ore by huge volumes.

Harold

 

[Ferrell]

Thanks, Harold. We didn't just have it assayed, we took it to a company that actually extracts the gold from the ore, as that's the most accurate way to know how much you can get. An assay shows how much is there, but you might not be able to actually extract that much. They had two samples of several lbs each, and averaged 7 ounces per ton of gold per sample (actual extraction).

We're not sure of the proper geological name, but we call it rotten rock. It's rock that can often be broken with your hands or easily smashed down to small pieces with a hammer. It's very easy and fast to break down to 100 mesh with a small rock crusher. A miner who looked at it believes it's a type of underground dunnite (sp?) tube from a nearby volcano, and we have watershed/springs in the area as well. We have been able to extract the gold, but don't know about the silver (there's about 4 ounces of silver per ton). We've been told it's a simple process to extract silver, and would like to know what the process consists of.

 

[Richard36]

Hello Ferrell,

That's some hot ore, wow.
Could you post some photos?
I'd like to see what you're processing.
It would help out as far as suggestions for processing too.

If you are actually working Dunite,
Platinum would be on the list of metals to be looking, and testing for.

Just my thoughts on the subject.

Sincerely, Rick. "The Rock Man".

 

[Ferrell]

Sure, I'll take some pics later today or tomorrow of the ore in it's natural state and the crushed product prior to cleaning. We won't be washing it, as it appears we're picking up part of the gold from the clay that surrounds the rock. We had tests run for Platinum and it was negligible, but it's possible it could be there, regardless. Would that be captured/extracted along with the gold when we're doing our SSN/Butyl/Oxalic extraction for the gold, or would we need to do something separate for platinum?

 

[Richard36]

I'm not sure what the abbreviation SSN stands for, at least at the moment, just waking up,
so I do not know if that particular process would work for PT.
My guess is that you would need a different precipitant to recover the PT, if in solution.

 

[Ferrell]

Richard, SSN stands for saturated salt mixed with Nitric Acid. I don't know what PT stands for. :lol:

 

[Richard36]

Richard, SSN stands for saturated salt mixed with Nitric Acid. I don't know what PT stands for. :lol:

Lol, funny.
Pt is the periodic table abbreviation for Platinum.

Does that salt and nitric trick actually work for you?
I tried that mix on some black sand with fine gold, and it didn't seem to do anything at all.
I ended up using Muriatic acid with Sodium Nitrate to make Poor Mans Aqua Regia to dissolve the gold from within the sand.

 

[Ferrell]

Yes, the SSN does work on our ore, but it might depend on the type of ore, I'm not sure. I know it didn't work on a batch when the outside temp was in the 60's during the day and high 40's at night, so we had to put it in a warm room in a sealed bucket to get it up to temp. It's also a good idea to do 7-1 or 8-1 on the salt vs nitric.
Can you tell me a bit more about the two chemicals you used and what kind of proportions and time/temp required? We're always open to checking other methods.

Also, do you know what process to use to extract silver? I haven't gotten any feedback on that yet.

Thnaks!
Miralee & Allen

 

[Reno Chris]

As Harold said, it depends on the form your silver is in. If its sulfides you might need some sort of flotation method, if its an oxidized silver mineral, cyanide might work. Your SSN will not work for silver as silver chloride is insoluble, and that insoluble material will remain with the ore.

 

[Macgiver]

Richard, SSN stands for saturated salt mixed with Nitric Acid. I don't know what PT stands for. :lol:

Lol, funny.
Pt is the periodic table abbreviation for Platinum.

Does that salt and nitric trick actually work for you?
I tried that mix on some black sand with fine gold, and it didn't seem to do anything at all.
I ended up using Muriatic acid with Sodium Nitrate to make Poor Mans Aqua Regia to dissolve the gold from within the sand.

The trick with SSN is making sure you have a super saturated solution of salt before you add the nitric. Once you add the nitric a lot of the salt will precip out. Then add iodine to make it more aggressive. :shock: My two point 6 cents.

CW

 

[butcher]

most silver compounds can be roasted to oxides, Iron added helps to convert sulfides.


I have no expierience with it but thiosulfate ammonium solution comes to mind.

Most any leach it would be best to determine the chemical makeup of your ore, then look into chemically converting it (either in roast or with chemicals in solution) and then leaching dissolving silver or other metals from solutionleaving it richer in silver content,
I would roast any ore as a pretreatment, and then there is also smelting to recover your ore.

first you need to know what you have, then make the plan of attack.

 

[Dirtdiggaler]

Try a 50-50 nitric acid water leach. Heat and when all reaction stops filter, then cement silver with pure copper and when you think your done add a drop of HCL if no white precip forms your finished cementing and smelt. To cement copper add tin then use wood ashes or sodium hydroxide to bring PH to 7 to dispose of acid properly.

 

[Toddntucson7]

My ore is CU, AG, PB, AU, MN, MO do I need to roast, crush then start? If it's a local oxidized in a carbonate limestone host? I added 50-50 nitric started leaching. What order do you pull elements? I don't want the worthless elements just AG and AU. It's a strong, hot, high grade consitrates at almost ^40 AG ton, grade of 684 g/mt with AG and PB being primary and gold a strong runner after @ 2.5 oz/ton. Do you leach, cement silver with copper, then PH with sodium hydroxide to a neutral 7 and pull your AU with stump out? Or is there an order? Do I have to cement the CU with tin then pull my AU? Do I do this at hot temps or cold? My rock has major AG with good PB and minor CU I would rather dump the low grade elements, pull the two if I can and smelt. Or send out in bars local then send to refinery to separate the AG/AU. Let me know thanks.

 

[butcher]

My ore is CU, AG, PB, AU, MN, MO do I need to roast, crush then start?

Start what? You only have a small list of metals what the ore is composed of? What other elements (arsenic, sulfides, carbonates...), without knowing what you have it is difficult to come up with ideas of what pre-treatments may work the best to prepare the ore for concentration or prepare the ore for an extraction processes, or what you may have to experiment with, to see what may work best. Before experimenting with a recovery process, then experimenting with a refining process you really need to understand what your dealing with...



If it's a local oxidized in a carbonate limestone host? I added 50-50 nitric started leaching.
Carbonates neutralize acids.
What order do you pull elements?

You have to concentrate and pre-treat before you can even worry about pulling elements.
But first you will have to find out what you are dealing with.


I don't want the worthless elements just AG and AU. It's a strong, hot, high grade consitrates at almost ^40 AG ton, grade of 684 g/mt with AG and PB being primary and gold a strong runner after @ 2.5 oz/ton. Do you leach, cement silver with copper, then PH with sodium hydroxide to a neutral 7 and pull your AU with stump out? Or is there an order? Do I have to cement the CU with tin then pull my AU? Do I do this at hot temps or cold? My rock has major AG with good PB and minor CU I would rather dump the low grade elements, pull the two if I can and smelt. Or send out in bars local then send to refinery to separate the AG/AU. Let me know thanks.

Your asking questions about refining when you have no clue about recovering the values from the ore.
Or even if you can mine it, and transport, or concentrate it or pre-treat it economically....

All you have at this point is gold fever, with no clue of what to do with the rock you found, or your gold fever.

Your gold fever is blinding you, and stopping up your ears from hearing reason, it is clouding your mind.

You are trying to put your plow in front of your mule, and then trying to pull them both to get your field plowed.

Lou has given you some very good advice to begin with, He has also made a thread to help you, and others with these types of questions.

Find a cure for that gold fever, and make your posts in that section, maybe we can be of help.

 

[galenrog]

Putting your questions and comments about the same ore in several threads makes for a confusing conglomeration. Please keep all questions about your ore in a single thread. It keeps things simple.

Moderators, could someone please review all of Todds' posts and put them in a single thread that allows this spread out mess to be more coherent? I, for one, have difficulty following the several threads that he has posted questions and comments concerning his ore. Thank you.

Time for more coffee.